2001 CHEVROLET C3500 HD lock

3-3 Heater and Air Conditioning Control
System (If Equipped)
Fan Knob
The knob located on the left side of the heating system
control panel regulates the fan speed. The knob has
four speed positions. To increase airflow, turn the knob
toward HI. To decrease airflow, turn it toward LO. To
turn the fan off, turn the knob to OFF. If you have the air
conditioner on, turning the fan knob to OFF also turns
off the A/C compressor.
With the fan knob in OFF while driving, the airflow will
be directed to the floor air outlets. The mode knob will
not redirect airflow to other selected outlet positions.
This is normal operation for OFF.Temperature Knob
The middle knob on the control panel lets you select the
relative temperature of the air flowing into the passenger
area of your vehicle. This knob will allow you to adjust
the relative air temperature independently of the fan and
knob settings. Turn the knob clockwise, toward the
red area, for warmer air. Turn the knob counterclockwise,
toward the blue area, for cooler air.
Mode Knob
The right knob on the control panel allows you to choose the
direction of air delivery. The knob can be placed in any
position between two mode settings to blend the flow of air. VENT: This setting directs air through the
instrument panel outlets.
BI-LEVEL: This setting divides airflow between
the floor air outlets and instrument panel air outlets.
HEATER: This setting directs air through the
heater floor air outlets.
BLEND: This setting directs air to the heater air
outlets and toward the windshield.
DEFROST: This setting directs air toward
the windshield.

3-4 Air Conditioning
On hot days, open the windows long enough to let hot
air inside escape. This reduces the time it takes for your
vehicle to cool down. Then keep your windows closed
for the air conditioner to work its best.
A/C: Press this button to turn the air conditioning on
and off. The system will cool and dehumidify the air
inside the vehicle when the A/C light is on.
Air conditioning will be automatically disabled when
the outside temperature drops below a level at which air
conditioning is ineffective.
With the A/C on, turn the temperature knob to MAX for
maximum cooling. This setting also puts the system in
the recirculation mode and helps to maximize your air
conditioner's performance and your vehicle's fuel economy.
RECIRCULATION: Pressing the
RECIRCULATION button limits the amount of outside
dust and odors entering your vehicle. This button will be
automatically disabled anytime the mode knob is turned to
BLEND or DEFROST mode. (The recirculation indicator
light will come on even though the recirculation button is
not selected). This setting also cools the air the fastest.
After the vehicle's interior reaches a comfortable
temperature, turn the temperature knob clockwise, to
place the air conditioning system in the normal mode.
Heating
The heater works best if you keep your windows closed
while using it. On cold days, use the HEATER or BI
-LEVEL
setting with the temperature knob in the red area.
If you use the engine coolant heater before starting your
engine in cold weather, 20
F (
-8
C) or lower, your
heating system will produce warmer air faster, to heat
the passenger compartment in cold weather.
The use of an engine coolant heater also reduces the
time it takes for the engine to reach normal operating
temperature, and shortens the time it takes the heater to
reach full output. For more information, see
ªEngine Coolant Heaterº in the Index.
Defogging and Defrosting
On cool, humid days, use BLEND to keep the windshield
and side windows clear. Use DEFROST to remove fog or
ice from the windshield in extremely humid or cold
conditions. Use DEFROST with the temperature knob
toward the red area and the fan control toward HI.

3-6
Ventilation Tips

Keep the hood and front air inlet free of ice, snow or
any other obstruction (such as leaves). The heater
and defroster will work far better, reducing the
chance of fogging the inside of your windows.

When you enter a vehicle in cold weather, turn
the fan to HI for a few moments before driving.
This helps clear the intake ducts of snow and
moisture, and reduces the chance of fogging the
inside of your windows.

Keep the air path under the front seats clear of objects.
This helps air to circulate throughout your vehicle.

The use of hood air deflectors may adversely affect the
performance of the heating and air conditioning system.Audio Systems
Your audio system has been designed to operate easily
and give years of listening pleasure. You will get the
most enjoyment out of it if you acquaint yourself with it
first. Find out what your audio system can do and how
to operate all its controls, to be sure you're getting the
most out of the advanced engineering that went into it.
Setting the Clock
Press SET. Within five seconds, press and hold the
SEEK right arrow until the correct minute appears on
the display. Press and hold the SEEK left arrow until the
correct hour appears on the display.

3-7 AM-FM Stereo
Playing the Radio
VOLUME: This knob turns the system on and off and
controls the volume. To increase volume and turn the radio
on, turn the knob clockwise. Turn it counterclockwise to
decrease volume and turn the radio off.
RECALL: Display the time with the ignition off by
pressing the recall knob. When the radio is playing,
press this knob to recall the station frequency.Finding a Station
AM
-FM: Press the lower knob to switch between
AM, FM1 and FM2. The display shows your selection.
TUNE: Turn the lower knob to tune in radio stations.
SEEK: Press the right arrow to tune to the next higher
station and the left arrow to tune to the next lower
station and stay there.
SCAN: Select either AM, FM1 or FM2 mode and press
both SEEK buttons to listen to a few seconds of each
radio station. SCAN will light up on the display.
The radio will automatically SCAN to the next higher
station, play that station for a few seconds, then SCAN
to the next higher station. Press VOLUME or both
SEEK buttons to stop scanning.

3-9 AM-FM Stereo with Cassette Tape Player
(If Equipped)
Playing the Radio
VOLUME: This knob turns the system on and off and
controls the volume. To increase volume and turn the radio
on, turn the knob clockwise. Turn it counterclockwise to
decrease volume and turn the radio off.
RECALL: Display the time with the ignition off by
pressing this knob. When the radio is playing, press this
knob to recall the station frequency.Finding a Station
AM
-FM: Press the lower knob to switch between AM,
FM1 and FM2.
TUNE: Turn the lower knob to tune in radio stations.
SEEK: Press the right arrow to tune to the next higher
station and the left arrow to tune to the next lower station.
PUSHBUTTONS: The four numbered pushbuttons let
you return to your favorite stations. You can set up to
21 stations (seven AM, seven FM1 and seven FM2). Just:
1. Turn the radio on.
2. Press AM
-FM to select the band.
3. Tune in the desired station.
4. Press SET. (SET will appear on the display.)
5. Press one of the four pushbuttons within five seconds.
Whenever you press that numbered button, the station
you set will return.
6. Repeat the steps for each pushbutton.

4-7
Avoid needless heavy braking. Some people drive
in spurts
-- heavy acceleration followed by heavy
braking
-- rather than keeping pace with traffic. This
is a mistake. Your brakes may not have time to cool
between hard stops. Your brakes will wear out much
faster if you do a lot of heavy braking. If you keep pace
with the traffic and allow realistic following distances,
you will eliminate a lot of unnecessary braking. That
means better braking and longer brake life.
If your engine ever stops while you're driving, brake
normally but don't pump your brakes. If you do, the
pedal may get harder to push down. If your engine
stops, you will still have some power brake assist. But
you will use it when you brake. Once the power assist is
used up, it may take longer to stop and the brake pedal
will be harder to push.
Anti-Lock Brakes (ABS)
Your vehicle has anti-lock brakes (ABS). ABS is
an advanced electronic braking system that will help
prevent a braking skid.
When you start your engine and begin to drive away,
your anti
-lock brake system will check itself. You may
hear a momentary motor or clicking noise while this test
is going on. This is normal.
If there's a problem with the
anti
-lock brake system, this
warning light will stay on.
See ªAnti
-Lock Brake
System Warning Lightº
in the Index.

4-8
Here's how anti-lock works. Let's say the road is wet.
You're driving safely. Suddenly an animal jumps out in
front of you.
You slam on the brakes and continue braking. Here's
what happens with ABS.
A computer senses that wheels are slowing down. If one
of the wheels is about to stop rolling, the computer will
separately work the brakes at each front wheel and at
both rear wheels.The anti
-lock system can change the brake pressure faster
than any driver could. The computer is programmed to
make the most of available tire and road conditions.
This can help you steer around the obstacle while
braking hard.
As you brake, your computer keeps receiving updates on
wheel speed and controls braking pressure accordingly.

4-9
Remember: Anti-lock doesn't change the time you need
to get your foot up to the brake pedal or always decrease
stopping distance. If you get too close to the vehicle in
front of you, you won't have time to apply your brakes
if that vehicle suddenly slows or stops. Always leave
enough room up ahead to stop, even though you have
anti
-lock brakes.
Using Anti
-Lock
Don't pump the brakes. Just hold the brake pedal down
firmly and let anti
-lock work for you. You may feel the
brakes vibrate, or you may notice some noise, but this
is normal.
Braking in Emergencies
With anti-lock, you can steer and brake at the same
time. In many emergencies, steering can help you more
than even the very best braking.
Steering
Power Steering
If you lose power steering assist because the engine
stops or the system is not functioning, you can steer
but it will take much more effort.
Steering Tips
Driving on Curves
It's important to take curves at a reasonable speed.
A lot of the ªdriver lost controlº accidents mentioned
on the news happen on curves. Here's why:
Experienced driver or beginner, each of us is subject to
the same laws of physics when driving on curves. The
traction of the tires against the road surface makes it
possible for the vehicle to change its path when you turn
the front wheels. If there's no traction, inertia will keep
the vehicle going in the same direction. If you've ever
tried to steer a vehicle on wet ice, you'll understand this.
The traction you can get in a curve depends on the
condition of your tires and the road surface, the angle at
which the curve is banked, and your speed. While you're
in a curve, speed is the one factor you can control.